Paper machinery



T. AGRONIN PAPER MACHINERY Oct. 6, 1959 3 Sheets-Sheet 1" Filed April 22,. 1957 INVENTOR.

TA N Y A GPON IN ATTORNEYS Oct. 6, 1959 T. AGRONIN 2,907,499

PAPER MACHINERY Filed April 22, 1957 3 Sheets-Sheet 2 IN V EN TOR.

BY TANY AGEON/N A TZQR/VEYS T. AGRONIN PAPER MACHINERY Oct. 6, 1959 Filed April 22, 1957 3 Sheets-Sheet 3 INVENTOR.

TANY AGRONIN A TTOENEYS United States Patent f PAPER MACHINERY Tany Agronin, Middletown, Ohio, assignor to Pandia, Inc., Hamilton, Ohio, a corporation of New York Application April 22, 1957, Serial No. 654,101

4 Claims. (Cl. 222-272) This invention relates to transfer valves and more particularly to an improved rotary valve for transferring material between differential pressure zones.

The invention has particular relation to a valve which is useful for introducing wood chips or similar cellulosic material into a continuous digester operating at elevated temperatures and pressures, and which forms a seal preventing the escape of pressure from the digester during such charging and discharging operations.

It is a principal object of this invention to provide a rotary valve of improved structure and operating characteristics for transferring material from a first zone at one pressure to a second zone at another pressure with a minimum loss of operating pressure or transfer of pressure between the two zones.

Another object of this invention is to provide such a rotary valve which incorporates a pair of rotor members for transferring the material from a common inlet to a common outlet. 7 i

Additional objects and advantages of the invention will be apparent from the following description, the accompanying drawing and the appended claims.

In the drawing-- l a Fig. 1 is an axial sectiontaken substantially on the line 1-1 of Fig. 2 and showing a rotary valve construction according to the present invention;

Figs. 2 and 3 are radial sectional views taken along the lines 2-2 and 3-3 respectively of Fig. 1;

Fig. 4 is an enlarged section on the line 4-4 of Fig. 1 showing the pressure equalizing and exhausting header construction;

Fig. 5 is a radial sectional view of a rotary valve according to the present invention incorporating a single rotor;

Figs. 6 and 7 are enlarged fragments of Fig. 5 show-- ingthe mechanism for sealing between the. casing and the side of the rotor; and

Fig. 8 is a section on the line 8-8 of Fig.5.

Referring to the drawings, which illustrate preferred embodiments of the present invention, the improved rotary transfervalve comprises a casing 10 including arcuately shaped side walls ll which have suitable linings 12 mounted on the concave faces thereof. A vertically extending generally rectangularly shaped wall 15 terminates in an outwardly extending annular flange 16 defining an inlet opening 17 having knife blades 19 mounted along opposite edges. thereof, and a generally downwardly extending wallv 20 having a similarly outwardly extending flange 21 defines a single outlet opening 22. l

. The ends of casing 10 are formed with outwardly 2,907,499 Patented Oct. 6, 1959 holes 26 for reception of bolts 27 which extend through flanges 25 and end plates 30 to secure the plates 30 on casing 10. The casing thus defines a transfer chamber wherein material can be moved or transported from the inlet to the outlet side of the casing for introduction to or discharge from appropriate treating apparatus, a typical example of such apparatus for which the valve of the invention is particularly suited being continuous digesting apparatus for cellulosic material to be used in the manufacture of paper.

A dividing member 32, formed integrally at each end 'With casing 10 as shown in Fig. 3, extends longitudinally gaskets 34 extend essentially throughout the entire length of dividing member 32 and are radially adjustable by a wedge-like member 35. Members 35 are situated between gaskets 34 and the arcuate surfaces 33 so that adjustment of threaded stud 36 will cause inward movement of the gasket to compensate for wear. The member 32 is shown as cored at 37 for reduced weight.

Two shafts 40 extend longitudinally through casing 10 and are journaled at either end in bearings 41 which are mounted in the end plates 30. A driving gear 42 is keyed or otherwise attached to oneend of each shaft 40, and the two gears 42 mesh with each other to turn the two shafts in opposite directions asshown. Either shaft may be connected in any suitable manner to 'a end by caps 47 and 'on the inner ends by glands 48 which urge gaskets 50 against dependent flanges on end plates 30. Caps 47 are held in position by bolts 51 and 52 which also draw ringlike members 48 against gaskets 50. The opposite ends of the shafts are similarly enclosed with the exception that the caps 47 are replaced by stuffing boxes 53 which cooperate with glands 55 and gaskets 56, the glands 55 being provided with tightening bolts 57.

The curved side walls 11 and associated curved surface 33 cooperate to form a pair of chambers connecting with the inlet 17 andoutlet 22, and a rotor is mounted in each of these chambers on one or. the other of the shafts 40, as by key 61, for rotation with the shaft in response to the application of a driving force to driving gear 42. Each rotor 60 has a radius substantially identical with the radius of arcuate side walls 11 and the arcuate surface 33 of dividing member 32 so that the outer periphery 62 of the rotor will slidingly engage these surfaces. The total angular extent of each curved wall portion 11 and its associated curved surface 33 is considerably less than 360, and these respective surfaces are spaced angularly to provide inlet and outlet openings 63 and 64 connecting each rotor with the inlet 17 and outlet 22. Each rotor 60 also includes a plurality of radially disposed material-receiving pockets 65 having a number of openings. or holes 66 constructed in the bot-f torn thereof for connection to longitudinally extending. fluid passageways 67, and each rotor 60 is also ,cored at v 68 for reduced weight.

Passageways 67 extend completely through the hull portion of rotor and connect to a header ring Which has three gas-transmitting recesses 71, 72 and 73 formed in the surface adjoining the end of the rotor. Each of the preceding recesses is connected through a pipe 74- either to a suitable source of pressure or to atmosphere so that the atmosphere as Well as the pressure in each of the recesses can be controlled. Header ring 76 can be maintained in contacting relationship with rotor 60 by a coil spring 75.

The flanges 8110f rotor 60 which extend outwardly be yond the longitudinal limits of pockets 65 carry sleeves 81 riding within a plurality of ring like gaskets 82. Gaskets 82 are in turn compacted by glands 83. which are secured to casing 11 by means of bolts 84, to force them against flange and assure a tight seal preventing the escape of pressure from pockets 65. Thus by rotatably supporting rotors 60 within casing 113 and in contact With arcuately shaped side walls 11 and also in contact with the sealing gaskets 34 in the arcuate surfaces 33, the interior of the casing is divided into a charging zone and a separate discharge zone 91. The separate zones 90 and 91 can then be exposed to differential operating pressures without the loss of pressure from one zone to the other. 7

In the operation of the present novel valve structure for charging a continuous pulp digester with cellulosic material such as wood chips or the like, chips are fed into charging zone 91} of easing 1h through inlet opening 17.

As the chips enter the charging zone, they fall into the rotor pockets 65 While the bottom of each pocket is connected through arcuate recess 71 of header ring 741 to the atmosphere. The exhausting of air or other trapped gas from the bottom of pockets 65 is beneficial in that it precludes or limits the possibility of trapped air pockets being present which would block proper feeding. During operation, the rotor pockets 65 move from dividing member 32 through charging zone 91) toward side Walls 11, and the material in each pocket is leveled by knife blades 19 as the pockets pass into sealing engagement with the side walls. Rotation in this manner provides a longer circumferential sealing area for the full rotor pockets as they rotate toward discharge zone 91.

When a rotor pocket begins'to open into discharge zone 91, the bottom of the pocket is supplied with steam from .the second recess 72. The steam introduced into the pockets should be at leastequal to and preferably slightly material such as the Teflon material referred to hereinabove and extending substantially the full axial length of the rotor. As shown in Fig. 6, the inner edge 122 of each of the bars 121 is rounded and of smaller width than the body of the bar for projection to a limited extent beyond the inner surface of the wall 105. Additionally, a hose 123 of rubbery material extends through each of the slots 120 outwardly of the bars 121 and is connected at '125 to a source of fluid pressure.

With this sealing construction, the bars 121 are continuously urged toward the rotor 110 under controlled fluid pressure, and as the solidportions of the rotor approach the wall 105, they engage these bars successively in sealing relation, the rounded edge 122 of the bar providing a camming action with respect to the rotor. The spacing of the slots 1% is preferably such that at all times, thereare two bars 121 in sealing engagement with the rotor, thus effectively preventing transfer of pressure between the adjacent surfaces of the rotor and the wall 105, and the number and spacing of the slots l20 and bars 121 may be varied as necessary to provide such proper sealing action in valves of different sizes. This sealing mechanism is equally adaptable to the double rotor valve of Figs. 14 in place of the gaskets 34, and conversely the gasket arrangement could also be used in the valve of Fig. 5.

While the forms of apparatus herein described constitute preferred embodiments of the invention, it is to be understood that this invention is not limited to these precise forms of apparatus and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.

What is claimed is: Y

1. A rotary valve for transferring material between differential pressure zones comprising, means defining a casing having aligned inlet and outlet openings on the said inlet opening and including a cylindrically curved 73 to atmospheric or possibly sub-atmospheric pressure to discharge the pressurized atmosphere received during passage through discharge zone 91. The removal of pressurized gas is helpful to the later charging of the pocket.

when it enters zone 911 since there is no gas present to in terfere with proper reloading of the pocket with chips.

Fig. 5 shows' a rotary valve which is similar to that described in connection with Figs. l-4 but incorporates only a single rotor. The casing 189 has an inlet opening 101 and an outlet opening 162, and the side walls 105 and 106 are curved about the same center, with the wall 105 being of lesser angular extent than wall 106 and both of these walls being'provided with liners 107 and 108. The rotor 110, which is shown as of the same construction as the rotors 60, is keyed on a driven shaft 111 which extends longitudinally through the casing 101 and is. provided with glands 1:12 and associated packing similar to the parts 81-434 in Fig. l. The pockets 113 in the rotor are provided with fluid passageways 114 corresponding to the passageways 67 as already described,

. and the .knife blade 115 corresponds in structure and 7, function to the knife blades 19 in Fig. 2.

The rotary valve 101) is also shown'as provided with.

a diflferent mechanism for effecting continuous sealing separate chambers connecting with both said inletopenr" wall portion facing and concentric with each of said cylindrical casing Walls to define therewith a pair of separate chambers connecting with both said inlet opening and said outlet opening, said cylindrical wall portions of said dividing member being of the same radius but substantially less angular extent than said cylindrical casing walls, a pair of rotors mounted for rotation in said chambers respectively and having pockets in the surfaces thereof for receiving material from said inlet opening, said rotors being proportioned for running engagement with said cylindrical casing walls andwall portions of said dividing member, and means for rotating said rotors in opposite directions causing said pockets to receive material from said inlet opening andto carry such material'along said cylindrical easing walls-for delivery to said outlet opening.

2. A rotary valve for transferring material between differential pressure zones comprising, means defining a casing having aligned inlet and outlet openings 'on the top and bottom thereof respectively, said casing including a pair of spaced opposed cylindrically curved walls having at least the major portions thereof located laterally outside the projections of said inlet and outlet openings, a dividing member extending through'said casingbelow said inlet opening and including a cylindrically curved wall portion facing and concentric with each of said cylindrical casing walls to define therewith a pair of ing and said outlet opening, said cylindrical wall portions of said dividing member being of the same radius as but substantially less angular extent than said cylindrical casing walls, a pair of rotors mounted for rotation in said chambers respectively and having pockets in the surfaces thereof for receiving material from said inlet opening, means for rotating said rotors in opposite directions causing said pockets to receive material from said inlet opening and to carry such material along said cylindrical casing walls and in sealing engagement therewith for delivery to said outlet opening, and sealing means forming a part of each of said cylindrical wall portions of said dividing member for sealing engagement with surface portions of said rotors between said pockets.

3. A rotary valve for transferring material between differential pressure zones comprising, means defining a casing having aligned inlet and outlet openings on the top and bottom thereof respectively, said casing including a pair of spaced opposed cylindrically curved walls having at least the major portions thereof located laterally outside the projections of said inlet and outlet openings, a dividing member extending through said casing below said inlet opening and including a cylindrically curved wall portion facing and concentric with each of said cylindrical casing walls to define therewith a pair of separate chambers connecting with both said inlet opening and said outlet opening, a pair of rotors mounted for rotation in said chambers respectively and having pockets in the surfaces thereof, means for rotating said rotors in opposite directions causing said pockets to receive material from said inlet opening and to carry such material along said cylindrical casing walls for delivery to said outlet opening, the angular extent of each said cylindrical casing wall being such that said wall simultaneously encloses a plurality of said pockets in the associated said rotor for pressure sealing engagement with the material in said pockets, each said cylindrical wall portion of said dividing member being of the same radius but substantially less angular extent than the associated said casing wall, and means forming a part of each said cylindrical wall portion of said dividing member for effecting a substantially pressure-tight seal with the surface of the associated said rotor between said pockets therein.

4. A rotary valve for transferring material between differential pressure zones comprising, means defining a casing having aligned inlet and outlet openings on the top and bottom thereof respectively, said casing including a, pair of spaced opposed cylindrically curved walls having at least the major portions thereof located laterally outside the projections of said inlet and outlet openings, a dividing member extending through said casing below said inlet opening and including a cylindrically curved wall portion facing and concentric with each of said cylindrical casing walls to define therewith a pair of separate chambers connecting with both said inlet opening and said outlet opening, a pair of rotors mounted for rotation in said chambers respectively and having pockets in the surfaces thereof, means for rotating said rotors in opposite directions causing said pockets to receive material from said inlet opening and to carry such material along said cylindrical casing walls for delivery to said outlet opening, the angular extent of each said cylindrical casing wall being such that said wall simultaneously encloses a plurality of said pockets in the associated said rotor for pressure sealing engagement with the material in said pockets, sealing means forming a part of each said cylindrical wall portion of said dividing member for sealing engagement with surface portions of the associated said rotor between pockets, and means for adjusting said sealing means to maintain said sealing engagement thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,854,148 Hunter Apr. 12, 1932 2,243,058 Wysong May 20, 1941 2,657,022 Spiess et al Oct. 27, 1953 2,766,911 Greaves et al. Oct. 16, 1956 

